Rise in Oral Cancers in Young Nonsmokers Tied to Immunodeficiency

Younger, nonsmoking oral cancer patients have a higher risk of death than that of young smokers, and the outcomes may be related to immune deficiencies. The finding comes from a database of oral cavity squamous cell carcinoma (OSCC) patients treated between 1985 and 2015.

"Recent studies have shown an association between high neutrophil to lymphocyte ratio as a marker for poor outcome in several different cancers. This ratio is a surrogate marker for a patient's immune function. A high ratio indicates an impaired immune function. This means that the ability for the immune system to identify and eradicate abnormal cells which have the potential to form cancer cells is impaired. We don't know why this is occurring," said Ian Ganly, MD, PhD, a head and neck surgeon with Memorial Sloan Kettering Cancer Center in New York.

Ganly is lead author of the new study, published online March 5 in Oral Oncology.

"Physicians should be aware these patients may have impaired immunity and may have a more aggressive presentation and clinical behavior. Such patients may require more comprehensive staging investigations for cancer and may require more comprehensive treatment. Following treatment these patients should also have a detailed and regular follow-up examination with appropriate imaging to detect early recurrence," he said in an interview.

The research also suggests that immunotherapy may be effective in this group. "However, our findings are only preliminary and further research into this area is required before such therapy can be justified," Ganly said.

The study comprised 2,073 patients overall (median age, 62; 43.5% female) and 100 younger nonsmoking patients (median age, 34; 56.0% female). After multivariate analysis, compared to young smokers, nonsmokers with OSCC had a greater risk of mortality (P = .0229), although they had a lower mortality risk than both smokers and nonsmokers over 40. After adjustments, young nonsmokers had a mortality resembling that of older patients, while mortality among young smokers was distinctly lower than that of older patients.

In a subset of 88 young nonsmoking patients, there was a higher neutrophil-to-lymphocyte ratio (median, 2.456) than that of similarly aged patients with thyroid cancer (median, 2.000; P = .0093) or salivary gland benign pathologies (median, 2.158; P = .0343).

The researchers are now studying the genomics of tumors found in smokers and nonsmokers and comparing them to tumors in older smokers and nonsmokers with OSCCs. They are performing a similar comparison of the immune environment of the tumors and patients' immune system function. "For the genomics aspect I am looking to see if there are any unique alterations in the young nonsmokers that may explain the biology of these cancers. If so, there may be some alterations that can be targeted with new drugs. For the immune aspect, our goal is to see if there are any specific alterations in immune function unique to this population. Then it may be possible to deliver specific types of immunotherapy that focus in on these deficiencies," said Ganly.

The study was funded by Fundación Alfonso Martín Escudero and the National Institutes of Health. Ganly has no relevant financial disclosures.

This article originally appeared on MDedge.com, part of the Medscape Professional Network.